Multi-tube fluorescent discharge lamp

ABSTRACT

A multi-tube fluorescent discharge lamp, which is constructed of multiple glass tubes of different caliber in coaxial structure, the both sides of the inner most tube are connected to a cathode respectively, by isolating, perforating and blocking the discharge path, forming a successive discharge path, and coating phosphor on surface of the discharge tubes. The Invention can then have more fluorescent area than a conventional fluorescent lamp of the similar size and higher lumen as well as power transfer factor. Compared with the power consumption of a conventional fluorescent discharge lamp, the Invention therefore has higher luminous flux.

Background of Invention

[0001] 1. Field of the Invention

[0002] The Invention relates to fluorescent discharge lamps, and moreparticularly, to a multi-tube fluorescent discharge lamp which isconstructed of multiple glass tubes of different caliber in coaxialstructure, the both sides of the inner most tube are connected to acathode respectively, by isolating, perforating and blocking thedischarge path, forming successive discharge chambers, and coatingfluorescent material on surface of the discharge tubes. The Inventioncan then have more fluorescent area than a conventional fluorescent lampof the similar size and higher lumen as well as power transfer factor.Compared with the power consumption of a conventional fluorescentdischarge lamp, the Invention therefore has higher luminous flux.

[0003] 2. Description of the Prior Art

[0004] Generally, a conventional fluorescent discharge lamp uses onestraight or round tube. To minimize the size and to increase theillumination, there is a kind of compact fluorescent discharge lamp thatthe straight tube is bent into a wreath or U type. Alternatively,couples of short straight fluorescent tubes are aligned and connected inparallel, on the both terminations of the tube with a cathode tungstenfilament that coated with oxide such as Ba, Sr and Ca. In the dischargetube is in a state of vacuum and with little Hg and Ar, which helps thedischarge.

[0005] The conventional fluorescent lamp tubes is usually a roundcross-section and only one layer of fluorescent material such asphosphor is coated on the surface of the tube inside. When the cathodeson both sides of the tube is started up by current and high-voltagepower is applied to the cathodes on both sides of tube, the electron isreleased between the two cathodes and make the tube glow discharge. TheAr and Hg vapor molecules are also stimulated to create plasma; the ionand ultraviolet rays also impact the phosphor, so that the potentialenergy is transferred into light from the phosphor.

[0006] Because the cross-section area of a round tube is larger thanthat of any shape, the average density of electronic flux of the roundtube inside is lower than other shape of tube. Furthermore, theelectronic flux on the discharge path is concentrated nearby the axis ofthe discharge tube; the density of the electronic flux nearby thesurface of the discharge tube inside gets lower.

[0007] Therefore, the luminous flux in a round tube can not inproportion to raise by increasing the diameter of the tube to expand thearea of phosphor, much of energy nearby the axis in the discharge tubewill be depleted and transfer into heat, the transferring factor of thelumen (Lm) and Watt (W) remains not high enough.

[0008] Although there is another kind of lamp which build-in a lot ofsegmented tubes and coated with phosphor to increase the illuminantfluorescent area, but the lamp does not forming a successive dischargepath, therefore, it does not guarantee stable discharge path or equableplasma status, nor adequate and complete illumination of fluorescentlayer in the discharge tube, because the discharge path proceeds in theshortest distance.

[0009] Moreover, due to the narrow spectrum of conventional fluorescentdischarge lamp, the color-rendering index (Ra) is low and the colortemperature (K) is high which therefore causes the illuminated objectunable to reveal its colors. Besides, for the cathode on both sides ofthe conventional fluorescent discharge lamp is hit by electron, thetungsten filament is then vaporized to be black and pollutes thefluorescent layer of the tube, hence reduces the illumination efficiencyof the fluorescent layer as well as the life cycle of the fluorescentdischarge lamp.

SUMMARY OF INVENTION

[0010] This Invention is a multi-tube fluorescent discharge lamp; thedesign concept of the Invention is constructed of multiple dischargeglass tubes of different caliber in coaxial structure. By isolating,perforating and blocking the discharge path, and applying phosphor onsurface of the discharge tubes, a thin and transparent film offluorescent coating is then created, allowing the light of the innertubes pass through each of the coatings to the outside of the lamp. Inaddition, a pair of cathodes as hot or cold cathode helps the electronicflux in the vacuum to be accelerated and hit the Hg molecule, which isthen stimulated to create plasma. The coating of fluorescent on theinner layer surface of the discharge tube is impacted by electron ionand UV rays and then to emits light. Under the same power rate and withthe same volume of lamp, the tubes of the multi-tube fluorescentdischarge lamp aligned in coaxial structure have smaller cross-sectionarea than that of conventional fluorescent discharge lamp so that thisInvention can allow higher density of electron flux to pass through thedischarge path in the tubes. Therefore, the high-density electron ionhas better stimulating effects on the fluorescent coating and theilluminant fluorescent area is larger than conventional fluorescentdischarge lamp, both advantages increasing the luminous flux.

[0011] Compared to conventional fluorescent discharge lamp of the samepower rate, this Invention is characterized by higher luminance, lowerconsumption of electric power and lower heat rate. Moreover, because theelectric flux of the Invention is less than that of conventionalfluorescent discharge lamp, the vaporization caused by electric fluxhitting the cathode gets slower and the life cycle of the cathode islonger accordingly than that of conventional fluorescent discharge lamp.It is also feasible to apply ringed cathode to increase the surface areaof the hitting of electron flux and then disperse the hitting, so thatthe oxide material on the surface of the cathode can be protected fromrapid consumption. By this way, the multi-tube fluorescent dischargelamp can outlive conventional fluorescent discharge lamp.

[0012] The multi-tube fluorescent discharge lamp whose surface is coatedwith various fluorescent material of different colors temperature. Thefluorescent material, being stimulated, can release fluorescence ofdifferent spectrum and create special colors after mixing. Alternativelyit can include wider spectrum to improve the color temperature (K) aswell as color-rendering index (Ra) to be close to the sun spectrum.

[0013] The multi-tube fluorescent discharge lamp is designed in coaxialstructure, aiming to achieve special colorful luminance or balancedspectrum range of light by way of filtering the luminance released fromthe transparent discharge glass tube of different colors.

[0014] The characteristics of this Invention can be specificallypresented by the following detailed figures.

BRIEF DESCRIPTION OF DRAWINGS

[0015]FIG. 1 is a partly broken side view of a conventional fluorescentdischarge lamp.

[0016]FIG. 2 to FIG. 9 are cross-sectional views and end views showing astep-by-step process of fabrication of a three-tube fluorescentdischarge lamp of a first embodiment.

[0017]FIG. 10 is a cross-sectional view and end view of the five-tubecombination with phosphor of a second embodiment.

[0018]FIG. 11 is a cross-sectional view and end view of an electrodeportion with a straight cathode.

[0019]FIG. 12 is a cross-sectional view and end view of an electrodeportion with a ring cathode.

[0020]FIG. 13 is a cross-sectional view and end view of a cap.

[0021]FIG. 14 is a cross-sectional view and end view of a cap combinedan electrode portion with a straight cathode.

[0022]FIG. 15 is a cross-sectional view and end view of a cap combinedan electrode portion with a ring cathode.

[0023]FIG. 16 and FIG. 17 are cross-sectional view to follow the FIG. 9showing a step-by-step process of fabrication of the three-tubefluorescent discharge lamp of the first embodiment.

[0024]FIG. 18 is a cross-sectional view of a three-tube fluorescentdischarge lamp of a third embodiment.

[0025]FIG. 19 is a cross-sectional view of a dual-tube fluorescentdischarge lamp of a fourth embodiment.

[0026]FIG. 20 is a cross-sectional view showing a five-tube portion anda pair of electrode portions of the five-tube fluorescent discharge lampof the second embodiment.

[0027]FIG. 21 is a cross-sectional view of the three-tube fluorescentdischarge lamp of the first embodiment showing a pair of basesunattached.

[0028]FIG. 22 is a cross-sectional view of the full schematic three-tubefluorescent discharge lamp of the first embodiment.

[0029]FIG. 23 is a cross-sectional view of the full schematic five-tubefluorescent discharge lamp of the second embodiment.

[0030]FIG. 24 is a partly broken and cross-sectional view of the fullschematic three-tube fluorescent discharge lamp of the first embodiment.

[0031]FIG. 25 is a partly broken and cross-sectional view of the fullschematic five-tube fluorescent discharge lamp of the second embodiment.

DETAILED DESCRIPTION

[0032] According to FIG. 1, illustrates a conventional fluorescentdischarge lamp.

[0033] The discharge tube 8 is a straight glass tube, on both sides ofthe tube are the cathodes 26 whose electrode 28 are connected to theterminal 42 of the tube base 40. The figure explains clearly that thereis only one phosphor layer 18 on the surface of the tube inside. Inaddition, because the density of electronic flux nearby the axis of thedischarge tube is higher than that the electronic flux nearby thephosphor layer 18 of the discharge tube inside. Therefore, much ofenergy nearby the axis in the discharge tube will be depleted andtransfer into heat, the power transfer factor of the lumen needs to beimproved.

[0034] According to FIG. 2, the first tube 10 is a round straight glasstube, which is the inner most tube in the multi-tube fluorescentdischarge lamp and are where the cathodes 26 located.

[0035] According to FIG. 3, to use as a flame of gas and oxygen or archeating around the circumference in the vicinity of the middle of thefirst tube 10 for softening and is rotated in the reverse directionaround both ends of the tube, and is twisted at the softening place thusfusing into an isolator 12 to seal the pipeline nearby the middle of thetube to insulate and separating the discharge path of the first tubeinto two discharge chambers.

[0036] According to FIG. 4, blowing the air in from both ends of thefirst tube 10, also heating is performed nearby both ends of isolator 12on the two circumferences at the position of plural number thus thethrough-hole 14 of plural number are formed.

[0037] According to FIG. 5, the second tube 16 is a round straight glasstube of which the diameter is slightly larger than that of the firsttube 10, at one end of the second tube 16 is air tight and the air isblown in from another end, or air is blown in from both ends, alsoheating is performed nearby both ends on the two circumferences at theposition of plural number thus the through-hole 14 of plural number areformed.

[0038] According to FIG. 6, the first tube 10, after passing through theholes, is slid into the second tube 16 in coaxial structure then heatingon the circumference of the second tube 16 correspond to the position ofisolator 12 of the first tube 10, also, rotation is made with reversedirection at both ends of the second tube 16, and is twisted at thesoftening place of the tube thus fusing into another isolator 12 withthe first tube 10 to seal the pipeline of the second tube 16 andseparating the discharge path of the second tube 16 into two dischargechambers.

[0039] According to FIG. 7, phosphor layer 18 is coated on the inner andouter layer surface of the first tube 10 and the second tube 16.

[0040] According to FIG. 8, the third tube 20 is a round straight glasstube of which the diameter is slightly larger than that of the secondtube 16, the phosphor layer 18 is coated on the inner layer surface ofthe third tube 20.

[0041] According to FIG. 9, this combination of the first tube 10 andthe second tube 16 can be slid into the third tube 20 in coaxialstructure.

[0042] According to FIG. 10 and refer to the FIG. 6, just as thecombination of the first tube 10 and the second tube 16 to be slid intothe third tube 20 in coaxial structure that the diameter of the thirdtube 20 which is slightly larger than that of the second tube 16,heating is performed on the circumference of the third tube 20correspond to the isolator 12 of the second tube 16, also, rotation ismade with reverse direction at both ends of the third tube 20 and istwisted at the softening place of the third tube 20 for fusing with theisolator 12 of the second tube 16, then to connect and form an isolator12 of the third tube 20 to seal the pipeline of the third tube 20 andseparate the discharge path of the third tube 20, to allow the air beingblown in at both ends of the third tube 20, also, heating shall beperformed on the circumference at both ends of 20 to approach theisolator 12 of the second tube 16 at the position of plural number thusthe through-hole 14 with plural number are formed.

[0043] Also, with a glass tube of the fourth tube 22, which the diameteris slightly larger than that of the third tube 20, to slide into thecombination of the first tube 10, the second tube 16, and the third tube20 into the fourth tube 22 in coaxial structure, heating on thecircumference of the fourth tube 22 approach to the isolator 12 of thethird tube 20, at both ends of said the fourth tube 22 is rotated inreverse direction, and twisted at the softening place of the fourth tube22 for fusing with the isolator 12 of the third tube 20 for connectingand forming an isolator 12 of the fourth tube 22 to seal the pipeline ofthe fourth tube 22, separating the discharge path of the fourth tube 22,thus forming two discharge chambers so that air can be blown in fromboth ends of the fourth tube 22, also, heating is performed on thecircumference to approach both ends of the fourth tube 22 and at theposition of plural number, thus extruding through-holes 14 with pluralnumber.

[0044] The phosphor layer 18 is formed at the inner and outer layersurface of the combination of the first tube 10, the second tube 16, thethird tube 20 and the fourth tube 22, also formed at the inner layersurface of the fifth tube 24. This connected combination of the firsttube 10, the second tube 16, the third tube 20 and the fourth tube 22shall be slid into the fifth tube 24 in coaxial structure.

[0045] According to FIG. 11, one stem 34 is a conical glass post, one ofits ends with smaller diameter can seal and fix the plural electrode 28which is connected with a straight form cathode 26, one pipe 32 isconnected with the sealed end of the fixed plural electrode 28, itsopening hole 30 is located the sealed end and communicated with pipe 32.

[0046] According to FIG. 12, and refer to the FIG. 11, the electrodes 28which is connected with a ring cathode 38.

[0047] According to FIG. 13, a cap 36 its inner diameter is same as theouter diameter of the first tube 10, the outer diameter of cap 36 is thesame as the diameter of the outer most discharge tube.

[0048] According to FIG. 14, the structure of stem is same as FIG. 11above, however, for the conical glass post, the larger end is connectedwith a cap 36, the outer diameter of said the cap 36 is the same as thediameter of the outer most tube of the multi-tube fluorescent dischargelamp.

[0049] According to FIG. 15 and refer to the FIG. 14, the structure sameas FIG. 14, however, its electrodes 28 is connected with a ring cathode38.

[0050] According to FIG. 16 and refer to the FIG. 9, also includingplural number stem 34, said stem 34 includes a cathode 26, pluralelectrode 28, and connects with a cap 36, said cathode 26 is assembledin the two discharge chamber of the first tube 10 respectively, theouter diameter of the cap 36 is the same as that of the third tube 20.

[0051] According to FIG. 17 and refer to the FIG. 16, the cathode 26 ofplural number stem 34 are slid into the two discharge chambers of thefirst tube 10 respectively, heating at the outskirts of thecircumference at both ends of all the tubes, melting and sealing bothends of the tubes.

[0052] Or use the cathode 26 of plural number stem 34 with cap 36 isslid into the two discharge chambers of the first tube 10 respectively,heating on the circumferences of cap 36 correspond to the both ends ofall the tubes, and at both ends of all the tubes can be melted andsealed. Due to the sealing of both ends of all discharge tubes andisolator 12 and through-hole 14 of the first tube 10 and the second tube16, thus, forming successive discharge chambers.

[0053] According to FIG. 18, the first tube 10 is a round straight glasstube, in which a pair of electrodes 28 and one pipe 32 with said tubeare slid in coaxial structure, and heating at one end of the tube forsoftening, by means of clamping, pressing and sealing the tube, the pairof electrodes 28 and pipe 32 can be fixed, air is blown into the pipe32, by means of the heating at the end of sealed, a hole 30 can beextruded, forming a phosphor layer 18 on the surface of said tubeoutside, install cathode 26 in the pair of electrode 28, and the otherfirst tube 10 can be completed with the method mentioned above.

[0054] The second tube 16 is a round straight glass tube, its diameteris slightly larger than that of the first tube 10, the air is blown inat both ends of the second tube 16, or one end of said tube is air tightand the air is blown in from another end, also, heating is performed onthe circumferences to approach both ends of the second tube 16, at theposition of plural number thus extruding the through-hole 14 with pluralnumber, and heating is also performed at the circumference to approachthe middle of the second tube 16, rotated with reverse direction at bothends of the second tube, and is twisted at the softening place of thetube thus fusing into an isolator 12 to seal the path of the dischargetube and separate the discharge path of the second tube 16.

[0055] The third tube 20 is a round straight glass tube, its diameter isslightly larger than that of the second tube 16, the phosphor layer 18is formed in the inner layer surface of the third tube 20 and in theinner and outer layer surface of the second tube 16.

[0056] The two cathodes 26 of the first tubes 10 can be slid into thetwo-discharge chamber of the second tube 16 in coaxial structurerespectively, that the cathodes 26 installed oppositely to approach theisolator 12, heating at the outskirts of the circumference at both endsof the first tube 10 and the second tube 16, sealing both ends of thetubes, then slid into the third tube 20 in coaxial structure, heating atthe outskirts of the circumference at both ends of the second tube 16and the third tube 20, sealing both ends of all discharge tubes. Due tothe sealing of both ends of all discharge tubes and isolator 12 andthrough-hole 14 of the second tube 16, thus, forming successivedischarge chambers.

[0057] As mentioned above, heating at the outskirts of the circumferenceat both ends of the first tube 10, the second tube 16, the third tube 20can make it soft and melt and seal both ends of all discharge tubes,also, a cap 36 can be placed at both ends of the multi-tube, after thecap 36 on the circumferences correspond to the both ends of alldischarge tubes is heated, both ends of the first tube 10, the secondtube 16, the third tube 20 can be melted and sealed, thus, formingsuccessive discharge chambers.

[0058] For the multi-tube fluorescent discharge lamp with more than Stubes, which can be formed by means of the method mentioned above withthe total tube number N (N=odd number), tube number of different tubewith different diameter, the isolator 12 can be formed from the secondtube 16 to the (N−1)th tube to approach the middle of the tubes. Thethrough-hole 14 with plural number can be formed at the even number tubeand from the second tube 16 to the (N−1)th tube to approach the bothends of the tubes at the position of circumference, the through-hole 14with plural number can be formed at the odd number tube from third tube20 to (N−2)th tube to approach the both ends of the isolator 12 at theposition of circumference.

[0059] The phosphor layer 18 coated on the inner and outer layer surfaceof the tube from the second tube 16 to the (N-1)th tube, and coated onthe outer layer surface of the tube on the first tube 10, and coated onthe inner layer surface of the Nth tube, a pair of electrode 28 of thecathode 26 connecting to terminal 42 of base 40 respectively.

[0060] According to FIG. 19, the first tube 10 is a round straight glasstube, heating is performed at the circumference to approach the middleof the first tube 10, and rotation is made with reverse direction atboth ends of the first tube 10, and is twisted at the softening place ofthe tube thus fusing into an isolator 12 to seal the pipeline of thefirst tube 10, thus, forming two discharge chambers, and air is blown infrom both ends of said tube and heating is performed at thecircumferences approach to the both ends, at the position of pluralnumber to extrude the through-hole 14 with plural number, forming thephosphor layer 18 on the inner and outer layer surface of said tube.

[0061] A second tube 16 is a round straight glass tube of which thediameter is slightly larger than that of the first tube 10, the phosphorlayer 18 is coated on the inner layer surface of the second tube 16,then the first tube 10 be slid into the second tube 16 in coaxialstructure, also, plural number stem 34, said stem 34 includes a cathode26, a pair of electrode 28, a hole 30, a pipe 32, its plural numbercathode 26 is placed in the two discharge chambers of the first tube 10.

[0062] Heating is performed at the outskirts of circumference at bothends of the first tube 10 and the second tube 16 to melt and seal bothends of the first tube 10 and the second tube 16 with the stem 34, dueto the isolator 12 and the through-hole 14 of the first tube 10, and thesealing of both ends of all discharge tubes, thus, forming successivedischarge chambers.

[0063] For the multi-tube fluorescent discharge lamp with 4 tubes ormore than 4 tubes, which can be formed by means of the method mentionedabove with the total tube number N (N=even number), tube number ofdifferent tube with different diameter, the isolator 12 can be formedfrom the first tube 10 to the (N−1)th tube to approach the middle of thetubes. The through-hole 14 with plural number can be formed at the oddnumber tube and from the first tube 10 to the (N−1)th tube to approachthe both ends of the tubes at the position of circumference, thethrough-hole 14 with plural number can be formed at the even number tubefrom the second tube 16 to (N−2)th tube to approach the both ends of theisolator 12 at the position of circumference, also, with one cap 36 orthe stem 34 connecting a cap 36 at both ends of the multi-tube to heatthe cap 36 at the circumferences of both ends of the correspondingdischarge tubes, both ends of all tubes can be melted and sealed, thephosphor layer 18 coated on the inner and outer layer surface of thetube from the second tube 16 to the (N−1)th tube, and coated on theouter layer surface of the first tube 10, and coated on the inner layersurface of the Nth tube, a pair of electrode 28 of the cathode 26connecting to terminal 42 of base 40 respectively.

[0064] According to FIG. 20 and refer to the FIG. 10, also includingplural number stem 34, said stem 34 includes a cathode26, a pair ofelectrode 28, and connects with one cap 36, said cathode 26 is assembledin the two discharge chambers of 10, the outer diameter of the cap 36 isthe same as that of the third tube 20. The cathode 26 of plural numberstem 34 is assembled in the two discharge chambers of the first tube 10respectively, heating is performed at the outskirts of the circumferencecorrespond to the both end of all tubes, its softening can melt and sealboth ends of all tubes or plural number stem 34 connecting with cap 36placed at both ends of the first tube 10, the second tube 16, the thirdtube 20, the fourth tube 22 and the fifth tube 24, heating on thecorresponding position at the circumference of all discharge tubes ofthe two cape 36 can seal both ends of all tubes. Due to the isolator 12,the through-hole 14 and sealing of both ends of all discharge tubes,thus, forming successive discharge chambers.

[0065] For the multi-tube fluorescent discharge lamp with more than 5tubes, which can be formed by means of the method mentioned above withthe total tube number N (N=odd number), tube number of different tubewith different diameter, the isolator 12 can be formed from the firsttube 10 to the (N−1)th tube to approach the middle of the tubes. Thethrough-hole 14 with plural number can be formed at the even number tubeand from the second tube 16 to the (N−1)th tube to approach the bothends of the tubes at the position of circumference, the through-hole 14with plural number can be formed at the odd number tube from the firsttube 10 to the (N−2)th tube to approach the both ends of the isolator 12at the position of circumference, the phosphor layer 18 coated on theinner and outer layer surface of the tube form the first tube 10 to the(N−1)th tube, and the inner layer surface of the Nth tube, a pair ofelectrode 28 of the cathode 26 connecting to terminal 42 of base 40respectively.

[0066] According to FIG. 21 and refer to the FIG. 17, one base 40 with apair of terminal 42 at both ends of the three-tube fluorescent dischargelamp, the electrode 28 of the cathode welded on said terminal 42respectively.

[0067] According to FIG. 22, when negative HV presents at one of thoseelectrode 26 in the first discharge tube 10, electrons released by itselectrode are attracted by positive HV at another electrode 26 inanother first discharge tube 10, for moving into second discharge tube16 from through-hole 14 of the first discharge tube 10, via the thirddischarge tube 20 from through-hole 14 of the second discharge tube 16;electrons passing through the third discharge tube 20 enter into anotherend of second discharge tube 16 from through-hole 14 thereof, and intoanother end of the first discharge tube 10 from through-hole 14 thereof,then the electrons hit another electrode 26; the electrode 26 withpositive charges are converted into negative charges during the nexthalf cycle of the alternating current, with negative charges in saidanother end of discharge tube 10, to release the electrons traveling inreverse along the route of electron movement of the first half cycle torepeat the process upon arriving at the corresponding electrode 26 withpositive charges during which electronic irons and ultraviolet excitedby the discharge chamber of each discharge tube, the phosphor on thesurface of each discharge tube will be impacted and to emit light.

[0068] According to FIG. 23, when negative HV presents at one of thoseelectrode 26 in the first discharge tube 10, electrons released by itselectrode are attracted by positive HV at another electrode 26 inanother first discharge tube 10, for moving into second discharge tube16 from through-hole 14 of the first discharge tube 10, via the thirddischarge tube 20 from through-hole 14 of the second discharge tube 16,then fourth discharge tube 22 from through-hole 14 of the thirddischarge tube 20 and finally into the fifth discharge tube 24 fromthrough-hole 14 of fourth discharge tube 22; electrons passing throughthe fifth discharge tube 24 enter into another end of fourth dischargetube 22 from through-hole 14 thereof, then into another end of thirddischarge tube 20 from through-hole 14 thereof and into another end ofsecond discharge tube 16 from through-hole 14 thereof reaching anotherend of the first discharge tube 10 from through-hole 14 thereof, thenthe electrons hit another electrode 26; the electrode 26 with positivecharges are converted into negative charges during the next half cycleof the alternating current, with negative charges in said another end ofdischarge tube 10, to release the electrons traveling in reverse alongthe route of electron movement of the first half cycle to repeat theprocess upon arriving at the corresponding electrode 26 with positivecharges during which electronic irons and ultraviolet excited by thedischarge chamber of each discharge tube, the phosphor on the surface ofeach discharge tube will be impacted and to emit light.

[0069] According to FIG. 24, at the related positions between alldischarge tubes, the isolator 12 formed at the first tube and secondtube to approach the middle of these tubes, the cathode 26 is located inthe discharge chambers of the first tube 10 respectively. Formingthrough-hole 14 with plural number at the circumference to approach theboth ends of the isolator 12 of the first tube 10, forming through-hole14 with plural number at the circumference to approach the both ends ofthe second tube 16. The phosphor layer 18 coated on the inner and outerlayer surface of the first tube 10, the second tube 16 and the innerlayer surface of the third tube 20, a pair of electrode 28 of thecathode 26 connecting to terminal 42 of base 40 respectively.

[0070] According to FIG. 25, at the related positions between alldischarge tubes, the isolator 12 formed at the first tube 10, the secondtube 16, the third tube 20 and fourth tube 22 to approach the middle ofthese tubes, the cathode 26 is located in the discharge chambers of thefirst tube 10 respectively. Forming through-hole 14 with plural numberat the circumference to approach the both ends of the isolator 12 of thefirst tube 10 and the third tube 20, forming through-hole 14 with pluralnumber at the circumference to approach the both ends of formingthrough-hole 14 with plural number the second tube 16 and fourth tube22. The phosphor layer 18 coated on the inner and outer layer surface ofthe first tube 10, the second tube 16, the third tube 20, the fourthtube 22, and the inner layer surface of the fifth tube 24, a pair ofelectrode 28 of the cathode 26 connecting to terminal 42 of base 40respectively.

[0071] Subsequently, Heating on outside of the combination of tubes;meanwhile, blowing in dry air from one of the pipe 32 and exhausted fromthe other pipe 23, to accelerate drying the phosphor layers. After thedrying process completed, one of the pipe 23 is heated and sealed, thenseveral mg of mercury (Hg) is injected into the discharge chamber fromthe opening pipe 32, then the discharge chamber is vacuumed and thenfilled with little of Ar gas such as several hundreds Pa in pressure,and then sealing the pipe 23. Afterward the combination of tubes is putin an environment of electromagnetic field such as microwave chamber toagitate the liquid Hg into vapor Hg, applying current and high voltageon the both cathodes, a glow discharge will be generated in thedischarge lamp.

[0072] It will be now apparent to those skilled in the art that otherembodiments, details and uses can be made consistent with the letter andspirit of the foregoing disclosure and within the scope of this patent,which is limited only by the following claims, construed in accordancewith the patent law, including the doctrine of equivalents.

1. A multi-tube fluorescent discharge lamp, comprising: A first tubewhich is an inner most tube; A second tube, which is slightly largerthan the first tube; and plural cathode, which are fixed on the two pairof electrodes and connected to the both sides of the first tuberespectively; wherein the tubes are constructed of different caliber incoaxial, coating phosphor on the outer layer surface of the first tubeand inner layer surface of the second tube, by isolating, perforatingand blocking the discharge path, forming a successive discharge path, inthe discharge chamber is in a state of vacuum and with little Hg.
 2. Thefluorescent lamp of claim 1, wherein said the discharge path isconstructed of the isolator which located nearby the middle of the firsttube, the through-holes which located nearby both ends of the firsttube, the plural cathode which located in the both sides of the firsttube respectively, the both ends of two tubes are sealed, forming asuccessive discharge path.
 3. The fluorescent lamp of claim 1, whereinfurther comprising multiple plural number tubes with the total tubenumber N (N=even), isolating from the first tube to the (N−1)th tubeapproach the middle of the tubes; forming through-hole at the odd numbertube from the first tube to the (N−1)th tube approach the both ends ofthe tubes, forming through-hole at the even number tube from the secondtube to the (N−2)th tube approach the both ends of the isolator, coatingphosphor on the outer and inner layer surface from the second tube tothe (N−1)th tube, and the inner layer surface of the Nth tube, and outerlayer surface of the first tube, the both ends of all tubes are sealed,forming a successive discharge path.
 4. A multi-tube fluorescentdischarge lamp, comprising: A first tube which is an inner most t secondtube, which is slightly larger than the first tube; A third tube, whichis slightly larger than the second tube; and plural cathode which arefixed on the two pair of electrodes and connected tot he both sides ofthe first tube respectively; wherein the tubes are constructed ofdifferent caliber in coaxial, coating phosphor on the outer and innerlayer surface of the first tube, the second tube and the inner layersurface of the third tube, by isolating, perforating and blocking thedischarge path, forming a successive discharge path, in the dischargechamber is in a state of vacuum and with little Hg.
 5. The fluorescentlamp of claim 4, wherein said the discharge path is constructed of theisolators which located nearby the middle of the first tube, the secondtube, the through-holes which located nearby both ends of the secondtube, the through-holes which located nearby both ends of the isolatorof the first tube, the plural cathode which located in the both sides ofthe first tube respectively, the both ends of three tubes are sealed,forming a successive discharge path.
 6. The fluorescent lamp of claim 4,wherein further comprising a fourth tube, which is slightly larger thanthe third tube; and a fifth tube which is slightly larger than thefourth tube.
 7. The fluorescent lamp of claim 6, wherein said thedischarge path is constructed of the isolators which located nearby themiddle of the first tube, the second tube, the third tube, and thefourth tube, the through-holes which located nearby both ends of thesecond tube, the fourth tube, the through-holes which located nearbyboth ends of the isolator of the first tube, the third tube, the pluralcathode which located in the both sides of the first tube respectively,the both ends of five tubes are sealed, forming a successive dischargepath.
 8. The fluorescent lamp of claim 6, wherein further comprisingmultiple plural number tubes with the total tube number N (N=odd),isolating from the first tube to the (N−1)th tube to approach the middleof the tubes. Forming through-hole at the even number tube from thesecond tube to the (N−1)th tube to approach the both ends of the tubes,forming through-hole at the odd number tube from the third tube to(N−2)th tube to approach the both ends of the isolator, coating phosphoron the outer and inner layer surface From the first tube to the (N−1)thtube and the inner layer surface of the Nth tube, both ends of all tubesare sealed, forming a successive discharge path.
 9. A multi-tubefluorescent discharge lamp, comprising: two first tubes are the innermost tube; A second tube, which is slightly larger than the first tube;A third tube, which is slightly larger than the second tube; and pluralcathode which are fixed on the two pair of electrodes and connected tothe one sides of the two first tube and installed oppositely in thesecond tuber; wherein the tubes are constructed of different caliber incoaxial, coating phosphor on the outer layer surface of the first tube,the inner and outer layer surface of the second tube and the outer layersurface of the third tube, by isolating, perforating and blocking thedischarge path, forming a successive discharge path, in the dischargechamber is in a state of vacuum and with little Hg.
 10. The fluorescentlamp of claim 9 wherein said the discharge path is constructed of theisolators which located nearby the middle of the second tube, thethrough-holes which located nearby both ends of the second tube, theplural cathode which are fixed on the two pair of electrodes andconnected tot he one sides of the two first tube and installedoppositely in the second tube to approach the isolator, the both ends ofthree tubes are sealed, forming a successive discharge path.
 11. Thefluorescent lamp of claim 9 wherein said further comprising multipleplural number tubes with the total tube number N (N=odd), isolating fromthe second tube to the (N−1)th tube to approach the middle of the tubes.Forming through-hole at the even number tube from the second tube to the(N−1)th tube to approach the both ends of the tubes, formingthrough-hole at the odd number tube from the third tube to (N−2)th tubeto approach the both ends of the isolator, coating phosphor on the outerlayer surface of the first tube and the inner and outer layer surfacefrom the second tube to the (N−1)th tube and the inner layer surface ofthe Nth tube, plural cathode which are installed oppositely in thesecond tube to approach the isolator, both ends of all tubes are sealed,forming a successive discharge path.
 12. The fluorescent lamp of claim3, 8 or 11 wherein the second tube is slightly larger than the firsttube, the third tube is slightly larger than the second, and the Nthtube is slightly larger than the (N−1)th tube, the (N−1)th tube isslightly larger than the (N−2)th tube.
 13. The fluorescent lamp of claim2,3,5,7,8,10 or 11 wherein said the through-holes which are formed onthe circumference at the position of plural number, extrudingthrough-hole with plural number.
 14. The fluorescent lamp of claim 1,4or 9 wherein said the discharge tube are transparent glass tube.
 15. Thefluorescent lamp of claim 1,4 or 9 wherein said the discharge tube aretransparent glass tube of different colors.
 16. The fluorescent lamp ofclaim 1,4 or 9 wherein said the cathode is fixed on the electrode pairof a stem which includes a pipe and a hole that communicated with thepipe.
 17. The fluorescent lamp of claim 1,4 or 9 wherein said the layersurface is coated with various fluorescent material of different colortemperature on the different layer surface.
 18. The fluorescent lamp ofclaim 1,4 or 9 wherein said the cathode which is straight cathode orring cathode.
 19. The fluorescent lamp of claim 1,4 or 9 wherein saidthe cathode is cold cathode or hot cathode.
 20. The fluorescent lamp ofclaim 1,4 or 9 wherein the discharge tube filled in little Ar.
 21. Thefluorescent lamp of claim 1,4 or 9 wherein also comprise plural base oflamp with plural terminal.
 22. The fluorescent lamp of claim 21 whereinsaid the plural terminal of the base connected to the electrodesrespectively.